Pole of inaccessibility to reach this false northern pole of inaccessibility was made by Sir Hubert Wilkins, who flew by aircraft in 1927. In 1941, the first Soviet expedition using an airplane landed 350 kilometers north of the false northern pole, thus actually becoming the first expedition to reach the real pole. Ignoring Soviet results, Sir Wally Herbert claimed to be the first to reach what was then considered to be the northern pole of inaccessibility on foot, arriving by dogsled in 1968. Explorer Jim McNeill claimed in 2006 that Herbert did not quite make the pole, and launched his own unsuccessful attempt
Doubt has perceived to be true from reasonable grounds, and consequently one must have the courage to continue doubting until one has found reliable grounds to satisfy the reason. Christian existentialists such as Søren Kierkegaard suggest that for one to truly have belief in God, one would also have to doubt one's beliefs about God; the doubt is the rational part of a person's thought involved in weighing evidence, without which the belief would have no real substance. Belief is not a decision based on evidence that, say, certain beliefs about God are true or a certain person is worthy of