In my experience, there is no "objective truth". All "truth" is colored by one's experience, and most severely by their senses. Because people don't literally share senses (in that we are not of one literal mind (think hivemind, like in the Alien movies), we can never be sure that what I experience is what you experience.
We can go through the processes of doing a legitimate science experiment, and a thousand other people can repeat the same experiment. But until we can achieve telepathy or thought sharing technology or powers, we can never be sure of having the same results.
To me, this is kind of depressing, that even two people who agree on everything might not really be agreeing, since they might be having two different experiences but calling it the same thing. Now, here's the question. What are your thoughts on this?