MD (retired), PhD, Jazz-mainstream-fan since the 1950's. Debut in 1968 as an amateur solo-pianist in Wassenaar, The Netherlands, during two cocktail parties at the home of Mr. W. R. Slee, Branch Manager of the First National City Bank, The Hague.  Former amateur-piano-player of the "House Town and Kitchen Washboard Players" - a Students Amateur New Orleans Jazz Band at Leiden University. Occasionally sitting in with the "legendary" Leiden Bakerstreet Jazzband (they won the 2nd prize at the regional "Braassemconcours") - until the late 1970's. 
In the autumn of 1971, however, this was temporarily alternated with accompanying (together with 12-string acoustic guitar player Mr. Bram Bol) the various stage actors in the Leiden amateur theater "Imperium" production : the musical "Grimmigheden" (based on Grimm's fairy tales), directed by the late Rein Edzard de Vries. This was well received (some newspaper reviews added, see below). 
In between, there was also time to sit in with “Padlás Puszta” (with Gerard “Bilstein” Bijlsma as the lead "primas" violinist, and Willem Raadsveld playing strongly-bowed double bass), the unforgettable Gypsy Quintet arising from the Leiden Student Choir and Orchestra Collegium Musicum (CM) in those years. In addition, this gypsy ensemble consisted of Mike van Tol, violin, Theo Krispijn, viola, Bas Schreuder, flute, and initially Eric Krul and later Hans van Waning, piano. The latter two pianists, however, left the orchestra and soon developed into accomplished amateur musicians especially on the Gypsy cymbal, after which your humble servant usually took over the piano playing within “Padlás Puszta”. If requested, this was regularly interspersed with lively dance music (foxtrot, swing) played on the piano, backed by the double bass. In this setting, an unmistakable nostalgia for the great Django Reinhardt's HCQ may have played some role too. In 1971 - 1972 (years of our Medical Master's) attending live performances by Mr. Ben Webster, receiving his signature and compliments, which proved to be true the rest of our lives. 
As a pianist accompanying, during rehearsals and a concert performance, the choir "Con Amore" (directed by Mr. Siem Cok) in our birthplace. Earlier, however, in 1966 with our father Jan, we had already been choral singers ourselves, in the street-evangelization-based interdenominational a-capella "Zaaiweekkoor" directed by Mr. H. J. ("Bert") Lemkes (a cousin of the renowned Dutch violinist and violin teacher Professor Bouw Lemkes). 
From 1972 solo pianist again, e.g. during wedding receptions, like the one in Aerdenhout, The Netherlands, at the home of pioneering Dutch cabaret performer & dentist Mr. Chiel de Boer in 1974. By the way, our great-aunt Anna was married to industrialist and amateur folksinger-songwriter Mr. Jan van Riemsdijk, whom she accompanied at the piano. See also https://www.de-veluwenaar.nl/2013/01/08/jan-van-riemsdijk/ 
From 1975 - 1979 trying out the swing jazz combo format with (semi-)professionals, such as Willem Raadsveld (bass) (not to forget our other influential amateur bass players like Johan de Kok and Ton de Goeij), and Alwin Schogt (clarinet).
Some more influences: our neighbour upstairs (1975-1977), living in the attic on the premises, playing trombone and musical saw in "The Original Michigan Ramblers of ArraWarra".

From 1980 pianist of the "Jazz Club Paramaribo" (leader Jan Simons, arranger Humphrey "Speen" Linscheer), also forming a local jazz trio with Eddy Li-Fo-Sjoe (sax) and Eddy Weltevreden (bass) in the Republic of Suriname, South America, until 1983. For a recent more historical review, see: https://www.academia.edu/66406763/K_J_van_Zwieten_2021_Facilitating_Dancing_for_Health_Retrospective_of_Some_Swing_and_Dance_Bands_in_the_West_Indies_1941_1981
 
Until 2020, sitting in with two colleagues (who play bass and drums) as a background jazz trio, during the cocktail party at our annual national assembly. While preparing for two upcoming local gigs (May/June 2015), the present series of solo recordings was realized. 
All added photographs were made at public performances (with free admission) over the years. 

A recent newspaper report of a 2015 local outdoor performance during a rainy April night with the slogan 'Music connects people', can be found at http://www.nieuwsblad.be/cnt/blboz_01658139
Next activities included guest appearances (“background piano music”) at Café De Pianist http://english.cafedepianist.nl/ Amsterdam, Summer 2016, and on August 1st, 2018 (for previous sets : http://www.dailymotion.com/video/x4uk0da). One deleted number can also be listened there at https://www.dailymotion.com/partner/x1uxpd6/media/video/details/x9ulq50 . Recently we added https://www.youtube.com/watch?v=yZ9x-0NZonQ

Especially in jazz-inspired piano music, to our opinion, there should be some hints of recapitulation - like in biology, ontogeny often contains elements of phylogeny. By playing piano this way, we can pay tribute to the musicians before us, who invented this wonderful kind of music ! Now to finish - freely paraphrasing St. Paul's advice to "remember those who led you" - ranged in chronological order my teachers in classical (piano) music were: Wouter de Jong, Cor de Man, Jan van der Meer, Mita Olaerts, Chantal Bohets (and Theo Paradis & Frans Vanbekbergen), Willy Appermont, Rudy Froyen, Hugo Lismont, Marc Caluwaerts, plus our parents and brother Jan and sister Reina.

This is my experimental music that may or may not see the light of day.

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