How do you go forward without any evidence?
Easy!
Rely on magic, superstition, wishful thinking, old wives tales, folklore, what the stars foretell and what the neighbors think, omens, public opinion, astromancy, spells, Ouija boards, anecdotes, Da Vinci codes, tarot cards, sorcery, seances, sore bunions, black cats, divine revelation, table tipping, witch doctors, crystals and crystal balls, numerology, divination, faith healing, miracles, palm reading, the unguessable verdict of history, magic tea leaves, new age mumbo-jumbo, hoodoo, voodoo and all that other weird stuff.
To this list I would also add philosophy and theology. As Heinlein noted:
Theology is never any help; it is searching in a dark cellar at midnight for a black cat that isn't there. Theologians can persuade themselves of anything.
Robert A. Heinlein
Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle
If a religion's teachings are true, then it should have nothing to fear from science...--dwise1
"Multiculturalism" does not include the American culture. That is what it is against.