| Victor Herbert musical: 1914 | 28 |
| Start of a quip from Mad Magazine | 33 |
| Robert Frost poem about a snowfall | 34 |
| Ann Sheridan | 12 |
| What nomads hit? | 16 |
| Part of some cultural nights out | 32 |
| Culture vultures' hangout | 29 |
| Instrumental gender counterpart? | 32 |
| Pulitzer-winning novel by Eudora Welty | 38 |
| Surgery locale, to an MD | 24 |
| Music by Ervin T. Rouse | 23 |
| English electronic group | 24 |
| Obsolete bass lute | 18 |
| Parkman's Italian cookbook? | 31 |
| Frontier way to the Northwest | 29 |
| Francis Parkman memoir | 22 |
| Something to prove | 18 |
| Pythagorean proposition | 23 |
| Mathematical proposition | 24 |
| Statement backed by a proof, in math | 36 |
| Rule expressed by an equation | 29 |
| Pythagorean nugget | 18 |
| Pythagorean ___ | 15 |
| Pythagoras' proposition | 27 |
| Prove it | 8 |
| Provable proposition | 20 |
| Proposition provable from accepted premises | 43 |
| Proposition deducible from basic postulates | 43 |
| Math statement | 14 |
| Logician's proposition | 26 |
| It may be proven | 16 |
| Idea accepted as true | 21 |
| Geometric law | 13 |
| Formulaic rule | 14 |
| Formula to be proven | 20 |
| Euclidean proposal | 18 |
| Corollary's kin | 19 |
| Axiom's kin | 15 |
| They get tested | 15 |
| Some of Euclid's discoveries | 32 |
| Ideas proposed as demonstrable truths | 37 |
| Formulas | 8 |
| Utah math proposition? | 22 |
| Concerned with hypotheses | 25 |
| Poiter film: 1971 | 17 |
| A. M. Lindbergh's "North to ___" | 46 |
| Murder mystery setting, to a cowboy? | 36 |
| Setting for a Christie classic | 30 |
| Theses | 6 |
| Scientifically accepted hypotheses | 34 |
| Hypotheses | 10 |
| Unfinished Charles Darwin work about mints? | 43 |
| Rock and Roll Hall of Fame doo-wop group from Baltimore | 55 |
| Creative thinker | 16 |
| Thinking person | 15 |
| Philosophical speculator | 24 |
| Impractical person? | 19 |
| Idea man, maybe | 15 |
| Speculative people | 18 |
| People with principles | 22 |
| Formulate a possible explanation | 32 |
| Speculation | 11 |
| Working hypothesis | 18 |
| Scientific statement | 20 |
| Relativity, for one | 19 |
| In ___ (hypothetically) | 23 |
| Darwin and Newton each had one | 30 |
| The butterfly effect or the big bang, e.g. | 42 |
| Speculative plan | 16 |
| Something to test | 17 |
| Something to be tested | 22 |
| Proposed explanation | 20 |
| More than a hypothesis | 22 |
| Keynesianism, for one | 21 |
| It's just an idea | 21 |
| Formulated idea | 15 |
| Big Bang ___ | 12 |
| B.C. rockers ___ of a Deadman | 29 |
| McGregor philosophy aimed at maximizing worker creativity | 57 |
| TV's Huxtable and Kojak, for two | 36 |
| T. R. et al., for short | 23 |
| Kojak et al. | 12 |
| Kojak and Van Gogh | 18 |
| Kojak and others | 16 |
| Kojak and a Huxtable | 20 |
| Huxtable boy and others | 23 |
| Baltimore team, in sportspeak | 29 |
| Baltimore baseball team, in sportspeak | 38 |
| Paramount pictures event | 24 |
| Big awards show, familiarly | 27 |
| Annual black-tie broadcast, familiarly | 38 |
| Group with the #1 hit "One Bad Apple" | 47 |
| Turn ___ cheek | 14 |
| Turn ___ check | 14 |
| End of January riddle | 21 |
| 1971 supernatural best seller | 29 |
| Sermon on the Mount metaphor | 28 |
| Pacifist's turn | 19 |
| Where extra words have been added to four answers in this puzzle | 64 |
| Part of a love triangle | 23 |