How can travel possibly have any significance other than as a pleasurable leisure activity?

Consider what is enveloping our human habitat: Not one of us will remain untouched if terrorism is allowed to run rampant, if the needs of fledgling democracies are not addressed, if chronic drug addiction continues on its relentless path, if the agonies of the hopeless and the homeless are not attended to, if our environment is further contaminated and if the proliferation of AIDS and other life-stopping viruses are not checked. There is no such luxury as isolation — our entire world community is at risk.

This concept of our planet as a global village was first promoted by Marshall McLuhan in the 1970s but is reinforced by every traveler who has left his footprint on foreign soil. The inter-relationship of nations and peoples and their economies and ecologies becomes clear to the thoughtful traveler. He recognizes that an abundant American wheat harvest may reappear as bread in Siberia, that a seal virus along the coast of Maine may result in hundreds of dead seals on the shores of Britain, and that religious zeal in one country may translate into terrorism in another.

I consider travel a teacher, a guide, the source of the greatest of all practical educations. What we learn in textbooks and from the news media pales by comparison with the impression gained from hands-on observation of the glories and the grislies of our globe.

The one indelible lesson I've learned in more than 40 years of globetrotting is that the aspirations of individuals inhabiting the thousands of cities and villages of Planet Earth tend to be similar. Ask and you will be told that they seek the peaceful conduct of their lives, in dignity, with as much personal autonomy and economic protection for their families as can be attained under disparate political and philosophic systems.

Whether communicating with a Stone Age clansman of Papua New Guinea, a Palestinian shopkeeper or an African cattle herder, the common baseline of our human aspirations is apparent. This commonality — as well as the differences inspired or determined by religion, politics and economic systems — cannot be conveyed accurately through surrogate eyes and lips. Television and newspapers are no substitute for direct visceral and cerebral reactions.

By opening his senses to direct imprint, a traveler may return to his home country to educate those within his sphere of influence. You could explain that people aren't stupid just because they don't understand or speak English. That draught and poachers are decimating the magnificent wildlife of Africa. That a designation on the World Heritage List will ensure the survival of our greatest manmade marvels.

From your travels, you would have observed that unchecked tourism to the Galapagos, Antarctica and the Amazon rainforest could threaten their fragile ecosystems. That introducing modern technology to self-sufficient peoples practicing traditional lifestyles is not necessarily desirable. That "progress and development" are not always beneficial.

What you experience abroad and how you process that sensory input can dramatically change your own pre-formed notions, propelling you toward becoming part of the solution, rather than part of the problem. And if that doesn't describe an excellent education, I don't know what does.

Irene Croft Jr. of Kailua, Kona, is a travel writer and 40-year veteran globetrotter. Her column is published in this section every other week.