FQXi 2014 asks, ‘How should humanity steer the future?' Recalling false obstacles to medical progress in humanity's recent past — eg, impeding Semmelweis (b.1818), McClintock (1902), Marshall (1951) — we reply, ‘Steer by Logic.' Then — with Logic in view and other scientific disciplines in mind — we amplify our answer via an online coaching-clinic/challenge based on Einstein's work. With the future mostly physical, this physics-based challenge shows how we best steer clear of false obstacles — unnecessary barriers that slow humanity's progress. Hoping to motivate others to participate, here's our position: we locate current peer-reviewed claims of ‘impossible' — like those from days of old — and we challenge them via refutations and experimental verifications. The case-study identifies an academic tradition replete with ‘impossibility-proofs' — with this bonus: many such ‘proofs' are challengeable via undergraduate maths and logic. So — at the core of this clinic/challenge; taking maths to be the best logic — we model each situation in agreed mathematical terms, then refute each obstacle in like terms. Of course, upon finding ‘impossibilities' that are contradicted by experiments, our next stride is easy: at least one step in such analyses must be false. So — applying old-fashioned commonsense; ie, experimentally verifiable Logic — we find that false step and correct it. With reputable experiments agreeing with our corrections, we thus negate the false obstacles. Graduates of the clinic can therefore more confidently engage in steering our common future: secure in the knowledge that old-fashioned commonsense — genuine Logic — steers well.