(H/T Rob Sica.) The organizers of Philpapers conducted a fairly extensive survey to determine what most professional philosophers believe about a range of issues. See their results and methods here. Some interesting results:
1. A priori knowledge: yes 71.1%; no 18.4%; other 10.5%.
2. Abstract objects: Platonism 39.3%; nominalism 37.7%; other 23.0%.
3. Aesthetic value: objective 41.0%; subjective 34.5%; other 24.5%.
4. Analytic-synthetic distinction: yes 64.9%; no 27.1%; other 8.1%.
5. Epistemic justification: externalism 42.7%; internalism 26.4%; other 30.8%.
6. External world: non-skeptical realism 81.6%; skepticism 4.8%; idealism 4.3%; other 9.2%.
7. Free will: compatibilism 59.1%; libertarianism 13.7%; no free will 12.2%; other 14.9%.
8. God: atheism 72.8%; theism 14.6%; other 12.6%.
[…]
28. Trolley problem: switch 68.2%; don’t switch 7.6%; other 24.2%.
29. Truth: correspondence 50.8%; deflationary 24.8%; epistemic 6.9%; other 17.5%.
30. Zombies: conceivable but not metaphysically possible 35.6%; metaphysically possible 23.3%; inconceivable 16.0%; other 25.1%