Dic: go on something (as meaning 'use as proof')

• But you have to go on the facts.
• There's not much to go on.
• The police don't have much to go on.
• Police haven't much to go on in their hunt for the killer.
• Since there were no witnesses, the police had little to go on.

* * *

△If you talk about the information you have to go on, you mean the information you have available to base an opinion or judgment on.

△(used in negative sentences and questions) to base an opinion or a judgement on something.

△[use as proof] to base an opinion or judgment on something.

△to base an opinion or decision on something.

..... COBUILD, OALD, LDOCE, Macmillan

CF. go on something

1. (Lit.) to begin something, such as a diet, rampage, drunk, etc. I went on a diet for the second time this month. Fred went on a rampage and broke a window.
2. (Fig.) to start acting on some information. We can't go on this! We need more information before we can act on this matter! Can you please give us more information to go on?

.... McGraw-Hill Dictionary of American Idioms and Phrasal Verbs

△ To base one's judgment on something; go by something:

• Going on the few symptoms that we could observe, we were able to diagnose the patient. 
• Without a witness, the police had nothing to go on.

..... The American Heritage® Dictionary of Phrasal Verbs