Summary
May and might are small auxiliaries that carry a great deal of meaning in academic prose. Both mark possibility, but they differ in tense behaviour, typical shades of probability, and whether they imply permission. Use the bare infinitive after them for present-time possibility (may/might + V) and have + past participle for past-time possibility (may/might have + V-ed). In reported speech and past-time framing, prefer might (backshifting): “I thought she might attend,” not “I thought she may attend.”
Semantics: In many contexts the two are interchangeable for epistemic possibility, but may often sounds a touch more probable or immediate (“Analysts may observe…”), while might can feel more hypothetical or remote (“Analysts might observe…”). Use may for granting, denying, or requesting permission (“May I…?” “You may not…”); avoid can when you mean permission rather than ability, and avoid might for permission in modern formal prose. For counterfactual conditions about the past, might have is the default: “If X had occurred, Y might have followed.”
Disambiguation and precision: “May not” can mean “is not permitted” or “possibly not”; write “must not / cannot” for prohibition and “might not / may or may not” for uncertainty. In scientific writing, prefer “may indicate/suggest/reflect” for cautious inference, and avoid overclaiming with “prove” or “will.” In legal/standards texts, may often encodes discretion (“is permitted to”), while shall/must encode obligation—do not mix them.
Bottom line: Choose may when you express present-time possibility, typicality, or permission; choose might when you backshift to past framing, mark weaker or counterfactual possibility, or avoid the “permission” reading. The guide below gives rules, nuance maps, decision trees, discipline-specific patterns, and dozens of copy-paste templates to help you deploy may and might with confidence in theses, articles, and reports.
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Using the Auxiliary Verbs Might and May Correctly in Academic Writing
Form, meaning, nuance, and discipline-specific guidance
Academic and scientific writing is a precision instrument. Small words carry large implications for evidence, certainty, time reference, and even ethics. Two of the smallest—and most consequential—are the modal auxiliaries may and might. Both are common vehicles for expressing possibility, but they also signal permission, probability, hypothesis, and counterfactuality. This guide sets out the core rules, then explores the subtleties that matter for theses, journal articles, grant proposals, and reports.
1) Form: how the grammar works
-
Present-time possibility: may/might + bare infinitive (no “to,” no
-s):
✔ “She may go.” ✔ “He might be right.” ✘ “Shemay goes.” ✘ “Hemight isright.” -
Past-time possibility (retrospective): may/might + have + past participle:
✔ “She may have gone already.” ✔ “He might have been present.” ✘ “Shemay went.” ✘ “Hemight was.” - Negation: place not after the modal: “may not,” “might not.”
- Questions: invert the modal: “May we proceed?” “Might this explain the discrepancy?”
2) Tense and backshifting: when context is past
Might historically functions as the past-tense counterpart of may. In modern English this shows up most clearly in backshift after past-tense reporting verbs and in clauses with past-time reference:
- Present frame → may: “We think she may attend.”
- Past frame → might: “We thought she might attend.”
- Retrospective inference → may/might have: “She may/might have attended, given the badge log.”
3) Semantics: possibility, probability, and nuance
For epistemic use (speaker’s assessment of what is true), may and might often overlap. Still, experienced readers hear a faint difference:
| Signal | Typical reading | Example |
|---|---|---|
| may | present-oriented, slightly stronger likelihood | “This polymorphism may influence drug response.” |
| might | more hypothetical/remote, or past-oriented | “In small samples, the effect might disappear.” |
Because the difference is subtle and context-dependent, do not overengineer it. If you need to grade confidence, pair the modal with a scalar adverb or verb (“likely,” “possibly,” “appears,” “suggests”).
4) Permission vs ability: may ≠ can
In formal writing, use may for permission and can for ability/capacity:
- Permission: “Students may submit electronically.” “May I cite the preprint?”
- Ability: “This assay can detect 10 copies per mL.”
5) Counterfactuals and conditionals
To discuss unrealized past conditions or hypotheticals, default to might (have):
- Counterfactual past: “If the sample had been larger, the interaction might have reached significance.”
- Remote present/future: “If resources were unlimited, we might extend follow-up to 5 years.”
May have is possible in counterfactuals but is less idiomatic than might have for many readers.
6) Fixed expressions and collocations
- may well + verb (“plausible/quite likely”): “The metabolite may well mediate the effect.”
- might (just) as well (“no better alternative”): “With the server down, we might as well draft the methods.”
- may as well (present-oriented; neutral); might as well (often past-oriented or slightly more resigned).
- so that … may (purpose, formal): “We anonymized IDs so that respondents may answer freely.”
7) Register and discipline notes
- Sciences & medicine: Hedge causal claims: “X may be associated with Y,” “Results may reflect measurement error.” Reserve “will” for planned procedures, not outcomes, and “prove” for mathematics.
- Humanities & social sciences: Use may/might to mark interpretive possibility: “This motif may index social anxiety,” “The policy might have emerged from fiscal pressure.”
- Law/policy/standards: may = discretionary permission; shall/must = obligation. Mixing them can misstate legal force.
- Formal correspondence: “May I request an extension?” is courteous; “Might I…?” is very formal/old-fashioned; “Can I…?” is informal (ability, not permission).
8) Disambiguating “may not” and friends
| Intended meaning | Prefer | Avoid | Example |
|---|---|---|---|
| Prohibition | must not / are not permitted to | ambiguous “may not” | “Participants must not eat after 20:00.” |
| Uncertainty (neg) | might not / “may or may not” | ambiguous “may not” | “The device might not trigger at low voltage.” |
| Uncertainty (pos) | may/might | “will” (if unsure) | “Early stopping may bias estimates.” |
9) Common errors and how to fix them
| Error | Why it’s wrong | Better |
|---|---|---|
| “She |
Modal must take bare infinitive | “She may go to the lab.” |
| “We |
Past frame needs backshift | “We thought she might attend.” |
| “The committee |
can = ability, not permission | “The committee may approve.” |
| “If enrolled earlier, they |
Counterfactual past prefers might have | “…, they might have improved.” |
| “Participants |
Ambiguous (prohibition vs uncertainty) | “Participants must not eat after 8 p.m.” |
10) A “hedging ladder” for results and discussion
Sometimes the question isn’t may vs might but how cautious to be. Combine modals with hedging verbs/adverbs to tune your claim strength:
| Stronger (still cautious) | Mid | Softer |
|---|---|---|
| “Results likely reflect …” | “Results may reflect …” | “Results might reflect …” |
| “Data support …” | “Data suggest …” | “Data are consistent with …” |
| “It is probable that …” | “It is possible that …” | “It cannot be ruled out that …” |
11) Decision tree (textual) for choosing may vs might
- Are you granting/denying/requesting permission? → Use may (“May we…?” “You may not…”). Do not use might for permission in contemporary formal prose.
- Is the clause anchored in past time (reported thought, past frame)? → Use might (or might have for past outcomes).
- Is it a counterfactual about the past? → Use might have.
- Otherwise, expressing possibility: Either may or might; choose according to nuance (present/typical vs hypothetical/remote). If probability matters, add “likely/possibly/perhaps.”
- Could “may not” be misread as prohibition? → Rephrase (“must not,” “might not,” “may or may not”).
12) Discipline-tailored templates (copy & adapt)
Life sciences / medicine
- “Elevated CRP may indicate systemic inflammation but might also reflect intercurrent infection.”
- “Patients receiving ≥10 mg/day may experience fatigue; clinicians may consider dose reduction.”
- “If randomization had been stratified by site, site effects might have attenuated.”
Engineering / physical sciences
- “Thermal cycling may degrade solder joints via intermetallic growth.”
- “At lower Reynolds numbers the wake might transition intermittently.”
- “In the presence of moisture, the polymer may hydrolyze; storage at ≤4 °C is recommended.”
Social sciences / humanities
- “The rhetoric may index shifting norms of authority.”
- “Given archival gaps, the alliance might have been more contingent than presumed.”
- “If the census had included migrants, urbanization rates might have appeared higher.”
13) “May” for typicality and risk statements
Academic and regulatory prose often uses may to mark possible but not inevitable outcomes—especially where safety or ethics are concerned:
- “Participants may experience mild dizziness.”
- “Investigators may encounter delays obtaining permissions.”
- “Use of the device may result in skin irritation.”
14) Subtleties worth knowing (but not overusing)
- “Might … but” for polite refusal / extreme improbability: “I might attend, but deadlines make it unlikely.”
- Dialect features to avoid in formal prose: double modals (“might could”), which are regionally valid but non-standard academically.
- “So that … may” vs “so that … can”: “may” sounds more formal/purposeful; “can” is plainer. Choose consistently with your register.
15) Practice: revise for precision
| Overstrong/ambiguous | Improved (with may/might) | Why it’s better |
|---|---|---|
| “The policy will reduce inequality.” | “The policy may reduce inequality, particularly among X.” | Appropriate caution |
| “We can use dataset Y.” | “We may use dataset Y (permission granted by Z).” | Clarifies permission |
| “We thought the catalyst may work.” | “We thought the catalyst might work.” | Backshift in past frame |
| “Subjects may not comply.” | “Subjects might not comply.” / “Subjects are not permitted to withdraw samples.” | Removes ambiguity |
16) Editing checklist (print before submission)
- [ ] Bare infinitive after may/might; have + past participle for past possibility.
- [ ] Backshift to might in past-time reported thought/speech.
- [ ] “May” used for permission; “can” reserved for ability.
- [ ] Ambiguous “may not” rewritten as prohibition (must not) or uncertainty (might not).
- [ ] Counterfactuals use might have.
- [ ] Hedging strength appropriate (may/might + suggest/indicate vs will/prove).
- [ ] Legal/policy texts maintain may (discretion) vs shall/must (obligation) consistently.
Conclusion: small words, large consequences
Choosing between may and might is rarely about memorizing “right vs wrong” and more about aligning time frame, communicative goal, and degree of commitment. Use may when you mean present-time possibility, typicality, or permission; use might for backshifted, hypothetical, or counterfactual contexts. When precision about probability or policy is crucial, combine these modals with explicit qualifiers (“likely,” “possibly,” “must not”) or with numerical evidence. With these tools—and the templates above—you can keep your claims calibrated, your ethics clear, and your prose unmistakably professional.
