Cover: Indivisible by Two: Lives of  Extraordinary Twins, from Harvard University PressCover: Indivisible by Two in PAPERBACK

Indivisible by Two

Lives of Extraordinary Twins

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Product Details


$23.50 • £18.95 • €21.00

ISBN 9780674025707

Publication Date: 09/30/2007

Academic Trade

288 pages

30 halftones


[A] fascinating explanation of the lives and experiences of twins… Segal’s book is a rich source of answered and still unanswered questions about twins and twinships, and it leaves us wanting to know more.—Frank J. Sulloway, The New York Review of Books

Nancy Segal…moves beyond the confines of the research laboratory, immersing the reader in the multifaceted uniqueness of living life as a twin. Using compelling illustrations of the twins’ entwined lives, Segal shows how the combination of an identical heredity and an unusual psychological closeness sustains lifelong similarities in wide-ranging psychological traits. At the same time, she offers many examples of the power of the non-shared environment to induce profound individual differences between pair members… Segal’s scholarly and literary talents make Indivisible by Two an informative, accessible, and pleasurable read for diverse audiences.—Laura E. Berk, Human Ethology Bulletin

[Segal] has interviewed and observed numerous sets of twins, recording the results in this fascinating study and engrossing collection of narratives… The connection between twins is irrefutably special; readers will no doubt be enchanted.—Lynne F. Maxwell, Library Journal

If you have even the mildest curiosity about how the lives of twins and multiples are woven together, you will want to read Nancy L. Segal’s new book, Indivisible by Two: Lives of Extraordinary Twins… Every story reveals fascinating insight into the physical and emotional ties that bind identical multiples. These glimpses into multiples’ lives raise questions about our own lives and families.—Kim Skublics, Multiple Moments

In Indivisible by Two, Professor Segal focuses on 12 diverse case studies of, almost exclusively, monozygotic (MZ; or identical) twins or higher multiples, Each example is so unique in its own way that the reader is left to wonder at the extensiveness of Professor Segal’s case notes that she is able to create a book with so many examples that are so different. It is a credit to her that so many twins and their families are willing to share their experiences with her, invite her into their lives and agree to have their stories included in a book. Her attention to detail, humor and chatty style will ensure the book’s appeal to a far-reading audience.—Naomi R. Wray, Twin Research and Human Genetics

Indivisible by Two by Nancy Segal is a feast of stories about monozygotic (identical) twins. It demonstrates the variety of unusual experiences that sometimes come with twinship.—Patricia M. Malmstrom, Twins Magazine

Each of the dozen stories provides fascinating reading… Each chapter in its own right provides insight into the special bonding between

What E.O. Wilson did for ants, Nancy Segal has done for twins… She has the ability to reach out and communicate with an infectious enthusiasm to both young minds and seasoned scientists.—Irving Gottesman, Irving and Dorothy Bernstein Professor in Adult Psychiatry, University of Minnesota Medical School

People have always thought that as twin athletes we were unique. Now, having read Nancy Segal’s book, we’re amazed at how many other twins can be so alike and so different at the same time. Indivisible by Two was a great read!—Paul and Morgan Hamm, Olympic gymnasts

A gripping collection of vignettes on an eternally fascinating phenomenon. Indivisible By Two is a wonderful book for its scientific implications, its human interest, and its literary quality.—Steven Pinker, author of The Blank Slate, How the Mind Works, and The Language Instinct

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