If you can't blindly trust that what you've been taught is true and accurate, who then can you trust? As a group, scientists are more worth listening to and trusting than most other voices competing to influence you.
What scientists have to say tends to be more accurate and trustworthy then what other leading voices have to say, not because scientists are better people than others (they aren't), but rather, because the things scientists say are based on the results of careful, systematic scientific study. Scientific methods are specifically designed to reveal the truth about things in a manner as free as possible from human bias, prejudice and expectation:
- Scientists take care to carefully and precisely measure the things they study using tools that are as accurate as they can make them.
- They set up their experiments in such a way as to minimize the impact of their own expectations and desires on their observed outcomes. For instance, they may set things up so that they do not know which group gets a treatment and which group doesn't get that treatment; by doing this they remove the possibility that they might treat the treatment group differently than the non-treatment group.
- Scientists submit their findings to peer-reviewed journals where editors go over every page of results looking for reasons to reject the findings due to methodological problems or inconclusive results. Only the strongest research survives this weeding-out process and gets published.
- Even after publication in a reputable journal, controversial research results are not taken seriously by the larger community of scientists until numerous separate scientists have independently verified the findings. Scientists only say things, then, when those things are exhaustively researched and supported by reliable, repeatably measured evidence.
Scientists' drive to uncover and describe the unvarnished and objective truth of things makes them worth listening to when they have something to say. While no one with an opinion is truly free from bias, scientists are, as a group, the most interested in uncovering the real truth, and the least interested in distorting their findings so that they will 'fit in' better with preexisting (and possibly wrong) cultural biases.
