There is, in Science, a sharp line between scepticism and denial. Scepticism is useful; it's what makes science tick. A scientist never assumes anything, she sorts fact from theory by setting up hypotheses and testing them.Denial is something else. Whereas a sceptic may doubt the theory, a denialist throws out the evidence.
"....the evidence that humans are warming the planet is in."
Mr van Tiggelen then goes to introduce diversions, such as tobacco, rather than looking at the Climate Realists' science. And infers senility. Shame on you. Look at the science. Look at the denials of the IPCC Climate Cabal CRU.